This invention relates to multi-component articles prepared from highly hydrogenated block copolymers. Specifically, it refers to articles produced from hydrogenated vinyl aromatic and conjugated diene block copolymers.
Multi-component articles, are articles having more than one xe2x80x98partxe2x80x99 or xe2x80x98componentxe2x80x99, such as articles containing both a rigid and an elastomeric component, e.g. an article comprising a transparent rigid lens and an elastomeric weather seal. Such articles are typically produced by individually producing each component separately, prior to assembly of the multi-component article. The components are typically made of different polymer compositions which are incompatible with each other in the molten phase. Therefore, recycle is not possible without first separating the different polymer components.
Multi-component articles have been produced from hydrogenated block copolymers and polyolefins as described in JP Kokoku 4-4130 by Asahi Kasei Corp. However, the hydrogenated block copolymer has very low aromatic hydrogenation and is modified with an additional functional group which would hinder compatibility of the polymer with the polyolefin for recycling purposes without component separation. For the purposes of this application, recycling refers to the reuse of a polymer material or combination of polymer materials such that the entire material can be reused as a sole component within an identical application without significant loss of polymer properties.
Therefore, there remains a need for multi-component articles in which the components can be recycled without costly separation processes.
The present invention is directed to a multi-component article which comprises at least two components, each component being produced from a different polymer composition, and at least one polymer composition comprises a hydrogenated block copolymer comprising at least two distinct blocks of hydrogenated vinyl aromatic polymer, and at least one block of hydrogenated conjugated diene polymer, characterized by:
a hydrogenation level such that each hydrogenated vinyl aromatic polymer block has a hydrogenation level of greater than 90 percent and the hydrogenated conjugated diene polymer block has a hydrogenation level of greater than 95 percent,
with the proviso that when more than one component is prepared from compositions comprising hydrogenated block copolymers, each composition differs compositionally such that the vinyl aromatic polymer block content of the compositions differs by at least 20 percent.
In another aspect, the present invention is directed to the multi-component article as described above, in which the components are adhered to one another without the use of adhesives.
These multi-component articles are fully recyclable, wherein the entire article can be reground without a component separation process to produce a polymer composition which has properties similar to those of the original materials, and can be reused as the sole material in the original applications.